https://www.ebay.com/itm/2-Pack-Kyde...Cclp%3A2334524
Kydex molds well with a blow dryer and cuts beautifully, molds to wooden bucks, easy to file and drill.
Or
Tractor supply sells a 1/2" thick rubber mat for about $20. It won't mold at all but it cuts nice. Heavy duty and very flexible.
Use big head aluminum rivets(for kydex) or use nutserts(for either) to attach.
$14 a pair for flaps, about $30 for tools.
Or
$15 gets you a selection of premade on Amazon.
But.
My 24.1 never flips anything up on the body so I won't be making any.
Signed,
Zappa's band.