Both Zoho CRM and Salesforce have a CPQ that would integrate. Depending on your complexity they could work.
Also ConfigureOne is one to look at
We’ve built a few custom built ones direct in NetSuite as well which can be more cost effective if your use case is not very complex
If your needing a CPQ that is more PSA or Saas based and less around physical product configuration you could try DealHub , Vendavo or ConnectWise