Beleive Tayside Aviation have some Aerobats, don't know how aerobatic they are, or if they are hired out for such use, but you can only ask!
There are also a few Pitts hanging around Perth, not for hire though I dont think
hope it helps,
Rusty.
P.S Tayside are at Perth, Dundee and Glenrothes. Excellent establishment with some nice aeroplanes!
Rusty.