Einstein TTC phono - Making Loading Plugs Help

My Turntable's Choice Unbalanced phono comes with 40, 85, 150 and 300 ohm loading RCA plugs. I need to make a "100ohm" loading plug. Measuring the true resistance of the plugs yields:

40 - 40ohm
85 - Not measured
150 ~ 220ohm
300 ~ 820ohm

So obviously I cannot use a 100hm resistor in this case. Any gurus can advise what resistor value I should use for an actual 100ohm loading for my Lyra Helikon SL cart?

Many thanks in advance!