I needed an exhaust/muffler nut for one of my Magnum XL .52 RFS engines. I tried searching the hardware store for it, but the fitting is an extra-fine threading that isn't commonly used for general hardware. I was told that a plumbing supply or HVAC company may have that kind of hardware on hand.

I decided to just pay $15.99 ($10 part plus $5.99 S&H) to Hobby People to ship me the replacement exhaust header with two nuts when I only need one of the nuts. I'd rather waste $16 and get my plane flying again rather than spend my precious leisure time looking for some obscure part.

Either money is more valuable than time, or time is more valuable than money. If you can't afford to waste an hour at your local hobby store, then pay the shipping. Buying an hour of free time for $5 is a bargain!