I am also Moss-free, after some inexcusably bad experiences with them. A couple suggestions for alternatives:
1. A lot of parts are generic and can be found in many places. That's where Moss and VB get some of their stuff. Take a look in the Spridgets section of the Wiki, Technical Tips. There's some info on parts. It would be great if other people could add to this.
2. My first priority is always to find a reconditionable, original part. It's almost always better than the modern replacements.
3. You can make a lot of your own parts. I'm not familiar with the gaskets you speak of, but in general, you can get all kinds of gasket material from a parts store, or on line, and make your own. You can even make thin gaskets out of brown grocery-bag paper (if you can still find a paper grocery bag!)
4. There are lots of people here who specialize in reconditioning certain kinds of parts, especially carbs, distributors, hydraulics, and shocks. Give them the business instead of just buying some slapped-together junk from M/VB.
In the end, getting unhooked from the Moss/VB axis will make it a bit more difficult to find things, but when you do, they'll be cheaper and the process of getting them will increase your resourcefulness. That's especially important if, some day, you want to restore a car where you don't have that crutch to lean on.
And, after all, M/VB don't have everything. You'll come up against this fact eventually, if you haven't already.