Good question! Run is open sourced and available on github as runoncomputer/sdk the actual db one needs to create to service a run based wallet is available at runoncomputer/run-db. It requires Node.js (I find v14.14.0 to work best) and python3. It will require some editing because at this time it calls many services that are no longer available.
There is a wallet available jdh7190/tique_case that you can freely modify to work in tandem with run-db. You can also change its config to use the same derivation path that relayx once did to use your BIP39 phrase, allowing access to your wallet.
That’s the summary of my experience. Last I used these, all the apis worked, and relay existed… it is 100% possible to regain access to a relayx wallet but everything must be built from scratch again.