Dave,
Don't know that SIG ever stopped making the Smith. I was in the market for one and was about to order direct from SIG when I found mine brand new in box on Ebay. Most of the SIG kits are made by them, but aren't usually stocked because they tend to be real builders kits. The Miniplane looks like it's gonna be fun, but you can tell it's an old design. I built the Sig Citabria with no problem, but they're definately old school compared to the newer GP and TopFlite kits.

If you're looking for the Miniplane, check to see if you LHS can order it or go direct to SIG's website.

Steve