So, 50 Ohm is not a E12 or E24 resistor value. As a result, if you want a 50 Ohm resistor, you tend to get quite expensive resistors, at least for through-hole.
So what are the options for getting 50 Ohm resistance? Ofcourse, since this is through-hole we are only talking about "low" frequencies, up to perhaps a few hundred megahertz. Options are:
51 Ohm resistors, these can often be found reasonably priced in hobby-user-volume (ie, where the difference between 1% and 5% is negligible)
Two 100 Ohm resistors in parallel.
47 Ohm resistors.
Any other tricks you can use to get cheap, simple and ok performing 50 Ohm resistance? I'm modding a video distribution amplifier to have 50 Ohm output impedance (even though I don't think it will make a difference for 10 MHz clock distribution).