Looking for postban buttstock, most websites only have the preban tele-stocks...

Call Rock River Arms or Bushmaster ...

ASA post ban M4 stock-
[url]http://www.brownells.com/aspx/NS/Store/ProductDetail.aspx?p=1441[/url]

Are there different types of M4 type stocks? different designs?

There are two types of Telestyled stocks.  You have the older "CAR" styled stock, which has no sling attatchment on the bottom but has a sling loop at the top of the stock.,  It's a bit smaller.  The Newer "M4" styled stock loses the top mount and has a sling attatchment on the bottom, the same as the A2 stock.  It's bas area is about the same size as an A2 stock.

As far as differences in the newer "M4" stock, Colt stocks are a bit rounder in the rear, while Bushmaster/RRA stocks have a sharper edge.  There is a thread floating around about the differences in Colt and Bushmaster stocks.

Any website that has all sorts of different stocks for ARs?