I've got a BSA 2.5 x 20 on my inline and it seems to be good. Not the best for sure, but it works well enough.
I found a Leupold on the web that should be good quality...
http://www.rifle-scope-store.com/item/49347_Leupold_Scopes_LEU_58450_FXII_ULTRLGT_2.aspx