Hello aastrakan,
Congrats on securing seed funds for your film. I suggest you carefully study the hundreds of US production companies and select 50 that are compatible with your project. Then contact them directly and discuss your project. I don't recommend you ask for money up-front. Instead, focus on what the Pro co. can offer you and why you think they are perfect for your project. No one is going to give you, or help you find funds, until after months of negotiation and discussion of the project.
If you have a good producer attached, he/she should be using a portion of the 300K to create a package for you to present to the US production company. (Fully developed, covered, and polished SP, talent attached, financing and distribution plan, legal team attached, etc).
Finally. Be very very careful about requesting funds in public forums. There are extremely strict securities laws in the USA that regulate film financing. Consult a US attorney before requesting money from anyone.
Best wishes.