Shopify iFrame / Javascript & API Integration and Theme Updates

I need support with integrating some iFrame/Javascript (provided) to allow us to have dynamic pricing across some of our products, as well as an API that will allow us to have a ring builder. We also require support in updating our Shopify theme without losing custom code and existing app integration.

Key Requirements:
- Integrate provided iFrame/Javascript for dynamic pricing
- Set up API for a ring builder tool
- Update Shopify theme while preserving custom code and existing app integrations

Ideal Skills:
- Shopify development expertise
- Experience with iFrame/Javascript integration
- API integration knowledge
- Proficient in Shopify theme customization without disrupting existing code

Please ensure you have relevant experience before bidding.