most auto parts shops will carry the hose size you need, but it will be a formed application based radiator hose. I had the same problem finding just straight universal hose as well.

What I did was bring the small section you pulled out, and ask them if you can go in the back and match the ID with the hanging radiator hoses that are there in abundance, then buy one, and the application will be random. Might cost 30 bucks for a full radiator hose, but you will be able to solve the problem, and have spare hose for 5-10 replacements

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