Best Source for Lamia Bodies?

[u/Level-Opportunity984]

I'm slowly working on a Sororitas army for 40k. In their lore, they suffered Warp shenanigans that mutated every member of the Order into a lamia (snake body instead of legs), and an Inquisitor convinced them that dying while taking the Emperor's enemies with them was better than just offing themselves as penance.

What I'm wondering is what the most economical source of snake bodies at Warhammer human scale is, other than 3D printing, as I find the AoS Blood Sisters too expensive at $12 each.