Talk to some local machine shops. I'm sure someone can help you out. Find out who your buddies are using. Find out who the pullers in your area are using.
What has been done to the engine?
That will help who ever does the work.
If it just needs rings and a valve job about any machine shop can help you out. If your wanting more performance done to it you may end up having to ship it if you can't find anyone local.
Just saw where you are at. If you can't find anyone local let me know. I can help. I don't know of any racers in your area. But I know a group a little south of you that don't race anymore. They may be able to help, but in the Yankton area.
I could help you out if you wanted to get the engine to the Council Bluffs, Ia area.
And shipping isn't that bad if you don't have to send the entire engine. Can you do any engine work yourself?