Well...I have recently been using the ORIGINAL strap locks which work great, are readily available, and economically viable.
Ya know those little plastic thingamajigs that come on bread bags? That's what we used before strap locks hit the market. They still work great, don't change the originality of the instrument, don't wear and tear the instrument, and, are a rather unique conversation piece should anyone happen to notice you using them.
Just a thought.