I need specific cactus recommendations

[Dewberry]

I live near Austin, Texas in zone 8b.

I’m planning to plant a couple bluish agave in my garden, and I’d like to plant a cactus or a succulent with them that has a different form from the agave’s form for contrast.

I’d like something with reddish skin or reddish spines (to contrast with the blue agaves). It should be fairly similar in size to the agave, so maybe a 12”-30” tall. It can be somewhat taller if it’s skinny enough not to block the plants behind it.

I’ll be giving it its own substrate as a low mound that it will probably share with the agaves. I can give it some winter protection if need be, or move it into an unheated greenhouse or my garage (maybe I’ll put a container halfway in the ground and bury it in cactus growing mix, and lift the container in the fall.

I think what may make this unobtainable is that I can’t wait more than about 3 years for the cactus to be the aforementioned size, and I can’t afford to buy a mature slow-growing cactus.

If you can think of anything that would work, please let me know.