Where can i purchase...?

Question

a 3.9 inch diameter elliptical nose cone? for a rocket

Answer 1

Ask to be built at a shop.  (Either metal or plastic).

Answer 2

I would imagine at any local hobbie shop

Answer 3

Hobby Lobby?

Answer 4

it is really hard to find this size of a nose cone so it much better to fabricate your own. you can use a wood mill or improvise a drill into a wood mill. good luck