Hi all, new to cycling and the forum, not really sure if this is the right place to post - but here goes. I recently bought a bike and it has Shimano grip shifts. I would really prefer the other ones (forgive me for my lack of knowledge) that are on the hoods which you click to go up and down. Think they're called SRAM or Ergo.

Was wondwering first of all would it be possible to replace my Grip-Shifts with these ones.
And where would I go to to buy these shifters online?

Thnx, Rick