Howdy, you don't have to buy custom but there are only so many places that sell tall top cowboy boots. They are sometimes called buckaroo boots.
https://drewsboots.com/ Drew's boots is in Eugene, Oregon and they carrt several tall tops. Check their list of Drew's Handmade Western Boots and Olathe Boots.
I have been buying boots through Solano's Boots and Western Wear in Raton, NM. https://www.solanoswesternwear.com/men/boots/tall_top.
Also check out Anderson Bean boots, by doing a web search you can find some tall tops.
in boots, Fred
: Through the years I've noticed when watching tv shows and movies, it seems that the shaft height of cowboy boots worn by men are taller than the standard 12 inch shaft. I've always wondered where you can purchase similar cowboy boots with the taller shaft and are they that common.