You can find several mini starters at many stores including NAPA or ebay or Summit or ebay etc.
I bought a Chevrolet Performance 3.375 ratio high torque for up to 11 to 1 compression Chevy Performance #19302919 from Summit and had to force my hand in my pocket to do it but it's hands down the best mini starter I've ever used (it should be too). It's a permanent magnet.I like this unit alot as it spins my engine easily wihout complaint and for the 374bucks it shoudbethe bad top of the drawer piece. Can be found on ebay for 225 or so. I paid 375 for mine. works like it should,