Well, my friend, I truely don't think that supercharging is the route to follow with a 305. You would be saving yourself a lot of coin, plus a lot of headache, if you just made that engine pump out its max. Naturally, this would involve better flow, so you may be wise to check out the other "305" topics on this site; just search for it using the "search" feature at the top of the page.
Honestly, although this may be strictly my personal opinion, to supercharge a 305 and expect anything great is nonsensical. You would probably see more performance gain by going with a larger displacement small block, all the meantime keeping the price below what it would cost to purchase a supercharger. Really, a 350 is a nice building platform that costs next to nothing. While a 305 CAN produce da juice, it just is not worth the hassle when you can get what you want from a larger cube engine.
However, if you insist on a blower with your 305, then yeah, you can hook up anything from a Paxton to a Wiand on a small block, but don't, not even for an instant, think that it will make your ride into a killer beast or anything. More than likely, you will gain bragging rights, a slight performance increase, and the shidder is that you also get an engine that will wear out in an instant. With this in mind, you are also better off "bragging rights" wise if you have a 12 second car that has NO nitrous, NO supercharger, and that YOU built at home.
These are my thoughts, not yours,