Within the last week, I have seen a posting refering to Harbor Freight's web site. They have a Topsider look alike for about $25.

I could not find that posting in this thread but if it was, sorry for wasting time.

Recently, I bought a powered unit (Jabsco) mail order because I had heard tales about Topsiders collapsing occasionally and some say they take a lot of pumping to get adequate vacuum.

I don't have the harbor freight link or would put it in here. Good luck.