depends on how much you what to spend.
on the low end there's the uncle mikes kydex holster that run about 20 bucks retail.
on the higher end the safariland 012, limcat, cr speed or ghost holsters will all work. all the race holsters are very adjustable, and with the exception of the safariland, the have a locking bar, that locks the gun in the holster.
you also might check out the IPSC matches at rio salado, there is always someone who got an old rig they are will to sell.