I got two of these Resistance Box 0-9999.9Ω Adjustable Lab Resistor Substitution Box Precision 1W Variable Knob Switch Boxes from AliExpress, but they kind of suck a bit. The resistors are only 1/4 Watt, the precision only 5% or 10%, and I had to mod it myself to replace the terminals with banana sockets.

Today I came across Build a Pro Decade Resistor Box for Cheap! PCB & 3D Print Files Included which includes all the plans necessary to make my own resistor box and with 1 Watt resistors.

I might take this on some time.