If by same size you mean "will the blade physically fit into the slot?", then the answer is yes.
If you mean "are the 32 and 357 blade heights the same?", then the answer is no.
A SP-101 parts list shows three different part numbers for the front sight blade for 22, 32, and 38/357/9mm - so this tells me they are different heights. Sorry I cannot you the height differences, just that they are different.
SP101 Front Sight W03602 - .357 cal., .38 Special, 9mm
SP101 Front Sight W03603 - .22 cal.
SP101 Front Sight W03604 - .32 H&R, .327 Fed. Mag.
(Info comes from the Illustrated Parts Breakdown in the back of a SP-101 Instruction Manual, which you can view on line at Ruger.com)