Glad you managed to work it out.
Regarding cheaper embedding models:
You should be able to use any embedding model provided that it uses the structure of the OpenAI Embeddings API Endpoint:
https://platform.openai.com/docs/api-reference/embeddings
Unfortunately that may rule out some providers - e.g. I tried running local embedding models using Ollama, but as Ollama is not OpenAI Compatible (yet) for their Embeddings Endpoint it doesn’t work.
As far as I know Deepseek currently does not have any embeddings models so you may have to cross them off the list…
I found some article that compares OpenAI vs Open Source Alternatives - that might come in handy for your further research on that topic: