I had an accident that broke of my rear derailleur and have to buy another one. I was thinking of taking the opportunity to get an upgrade.

I want to have a little higher final speed without loosing my hilly capacity but didnt found any cassete with less then 11T. If theres something with 10-32T on the market that would do for me. Is there?

My currently setup is 11-32T behind and 52T in the front.

Was thinking of buying this 44-55T chainset but Im not sure if the rear derailleur will be enough for a good chain tension.

Resuming, my questions are:

1) are there 10-32T cassetes on the market? where?
2) if not, will my dahon speed p8 need what rear derailleur to fit a 44-55T in the front and 11-32T in the back with good chain tension? The "Dahon Neos 9 Rear Derailleur" will do it?