If having an in-house server is your thing, there are plenty beefy rackmount units available on Ebay, from multi-blade clusters to single-image 8-way machines. Single thread performance will be worse, but throughput is still pretty impressive.

Also, multi-socket machines are much more interesting than single socket ones. Plus, if Rust is your thing, the very non-uniform NUMA topology will be an endless source of cool problems to solve (and I mean that - I love solving odd problems and inventing problems to solve myself is much less interesting).