If anyone is interested, I did pick up some spring straps that look to work quite well. I will pick up some larger #8 screws to fit tighter in the fin mounts, but the included screws would work fine too. I think these will be great to fit my rock boots, add a little weight, and make it easy to change between straps.
Highland Technical Spring Straps — XS Scuba - Everything For The Perfect Dive
Spring heel fin straps are popular because they are comfortable, easy to use and practically indestructible. Highland premium spring fin straps are made from stainless steel springs and covered with nylon tube webbing to protect the spring and keep out grass and other plant matter. The thumb puller
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