RV-4 exhaust cabin heat muff parts

I need to replace some or all of the cabin heat muff parts on my RV-4.

I am told I have a Vetterman exhaust system, but would appreciate if anyone could verify that with the provided picture.

Also, Aircraft Spruce only seems to sell the full exhaust kits, not the cabin heat muffs.

I looked at Vetterman's website and it directed me to robbinswings.com for questions on heat muffs; however, the website does not appear to work.

Does anyone have any information on where I might purchase replacement cabin heat muff parts for my RV-4?

Try this info Phone: 303-423-7002
[email protected] for robbins wings. The web page is active

I just got some replacement hardware from Rick Robbins yesterday.
quick friendly service if you call him by phone.

Thanks for your help. I contacted Rick at Robbins Wings and I will be getting the right parts shortly.