There are some light duty commercial units by well known companies, around $500 (if you look) by Anvil (7200), FMA Omcam (mt500), and MiniPack (Fast Vac). By all means check the warranty and replacement part availibility situations before buying.
I've got a friend who's had good luck with a 15" Cabela's -- which is really a rebranded Weston. If you look, you can find the Weston in either powder coat or stainless for well under $400 new. I don't think he uses his as much as you use yours though.
I've had good experiences going through Restaurant Equipment World for several purchases -- although not a vacuum sealer. They do have a "Vacuum Sealer World;" and you might want to browse the site.
Vacuum Sealer World - Commercial vacuum sealing equipment by Restaurant Equipment World
It looks as though they've got an amazing deal on the Orved (Eurodib) EVS at $700, but I'm a sucker for anything with a gauge. One of the nice thing about the REW people is they are very good on the phone, speak knowledgeably, give good advice to the limit of their knowledge based on your needs and not their potential profit, and say "don't know," when they don't.
By way of example, a couple of years ago I went nuts and tried to spend several hundred on a big deal blender and they talked me way down to the little 3/4hp commercial model we own and love. Less than $100, it saved me about $300 compared to what I was going to spend, and about $50 compared to what I would have spent for the same thing almost anywhere else.
Consider them endoresed.
BDL