Huge collar mount

Ordered a tripod collar and it seems that almost every one for sale on ebay or amazon is much bigger than the lens adapter. Mine is 3in in diameter on the inside while the LA5 is 2.5in, meaning I would need a 1/2in of filler to make it snug. Thats a lot of packing. G Houghton on youtube used electrical tape, but even in his video it didnt seem that he needed the hefty load I would require to make this safe. Is there another size collar I can get, or do I pack the heck out of this one filling it with velcro, carpet or whatever else Ive got?

Charles