Some time last year someone posted that Banggood had 50 ohm feed-through terminators for what is a reasonable price(6.66 USD shipped for a pair). I ordered a pair in December last year but they never arrived and a few months back Banggood issued me a refund. I was shocked yesterday when they arrived. It only took 7 months...
I did a quick check with a DMM and found one was near 50 ohms, the other though is 100 ohms - so quality control may be an issue.
Long story short the 50 ohm one actually works reasonably well.
Here is a picture showing SWR(return loss). I wouldn't really want to use these at 1 GHz but that shouldn't ever happen as any scope with such a high frequency will have a builtin 50 ohm terminator. For those with scopes up to 500 MHz without builtin 50 ohm terminators these will do the job though.
Resistor is close enough: