I am new to fly fishing and have caught a few steelhead on my 5wt rod. I would like to set up a 10' 7wt rod for steelhead. I would appreciate any suggestions as to what reel for these strong fast running fish.

Lamson is always a good bet. Read lots of online reviews. Machined aluminum is going to be typically lighter and more durable than cast aluminum. I have a couple lamsons myself so I may be a bit biased, but they seem to generally have a great reputation.

Ditto on the Lamson reel. I've been using a Lamson Radius 2.0 for the past 12 or so years and I'm very satisfied with it. The Radius 2.0 is not available anymore but the Lamson Guru is the closest to it. It's about $200.00 retail but this is the time of year to watch for sales. Check out www.mrfc.com , I think they have the Lamson Guru HD (in 6 weight ) on sale for about $160.00 . I've never fished for steelhead but I've handle some big trout (24" plus) on the Yough and the Lamson drag system is very nice. It may sound pricey, but I'll guarantee you'll only have it for a lifetime. Hope this helps and I wish you and everyone on the board a happy and healthy new year. Let us know how it works out.
P.S.
       Look under MRFCs' clearance section of their site. Good Luck, Matt.

http://www.fishusa.com/product/Waterworks-Lamson-Guru-II-Fly-Reels the guru is discontinued. It's been replaced by the guru II. The spare spools are not interchangeable. so if you plan on buying a reel now and possibly a spare spool later, get the new model as I went through this same thing with their last discontinued reel, the konic II. I was unable to find a spate spool when I wanted one. Still a great reel though.

Cast aluminum is basically making a mold and pouring liquid aluminum into the mold.  Machined is taking a block of aluminum and cutting away from it to produce the reel.  Machined is more durable in the long run.
 
If you're fishing in the bitter cold, then don't discount a sealed drag.  Not only will it help from getting sand and silt in your drag system but it will also prevent your reel from freezing up in below freezing days on the stream.  That typically will cost you more for a reel, but on days when my friends are dunking their frozen reels in the water to free them up for a few minutes or busting off fish because their drag is frozen solid, it's money well spent when my reel is still working fine.

I fish a 10' 7 wt also. My favorite reel for this rod, steelhead, is a Hardy Perfect Taupo. Pricy at around $700 but worth the money & with care will last a lifetime. Love click/pawl reels. Another great clicker reel is the Abel Switch, $500. Expensive, but worth the money. The 10' 7 wt I fish is a two piece Loomis glx classic. sweet, sweet rod for the Erie tribs. If you fish steelhead a lot it pays to get the best rod, reel you can afford. Lots of other good choices out there.

I don't even have a combo that would hit 500 bucks even if you count the line, for erie steelhead, especially PA I think paying that much is a little overkill, unless you have the money to pay for it, then feel free, but I have seen everything from cheap cabelas reels to more expensive things that I wouldn't imagine buying, with that said I have an Allen reel for my 7wt, little on the heavy side but it balances with my rod, so I am good. Just look at what is in your price range and find the best deal you can.

I'm with dux+deer, I've been using an Orvis Battenkill disc since they introduced the reel, and it is a fine unit (probably costs a lot more today than I paid back when they first came out!), and has held up like a champ!

You can't go wrong with Lamson for an even price to quality ratio. My Konic is my go to 7/8 wt Steelhead and light Saltwater reel.

Cabela's has incredibly affordable options like the Wind River reel. Unbeatable price when it's on sale, and they actually use Lamson technology for this particular reel. However, it's not as durable as the Lamson products themselves.

I also use Okuma SLVs. Another great reel for the price. It's biggest down fall is durability. If you drop it on a rock or knock it off the shelf in your basement or garage, expect it to crack or warp. Sometimes to the point where it's unusable. 

I fish a 10' 7 wt also My favorite reel for this rod, steelhead, is a Hardy Perfect Taupo. Pricy at around $700 but worth the money & with care will last a lifetime