Just replace the snap with a magnetic catch. They aren't really pricey, and the hardest part for me was getting the riveted snap out. Check with a tailor or even a tack shop and they probably have a simple trick for it. I wound up having to drill mine. I'm still surprised the sporran was unscathed when it was done!

Or just carry a few bucks and ID in you hose and leave everything else at home?