As the OP probably knows, straight-leg pants aren't the usual recommendation for ankle carry. Here's a quick way to save yourself some time/money to determine if a less bulky ankle rig MIGHT work for your gun/holster combo:

==>> Duct tape your gun in place around your sock and try it with your pants. Does it conceal? Can you reliably access the grip?

If that doesn't work, then you're never going to find a less bulky ankle rig.

If it does, then MAYBE it's possible to find one, maybe, but you have to work within the current limits of current material technology.