+1 on junk yard rescue and rebuild yourself.
For those above who asked, where is the intermittent relay?
124 and 126 it is N10 relay, the second largest relay in the box. This also carries your turn signal flasher and rear defroster control/timeout. These are all straight wired circuits, fuse to switch to motor.
The intermittent relay pulses the motor off and on intermittently. What it actually does is makes the motor go into a “wipe once then park” just the same as if you twisted the switch to II and then back to 0. I did a writeup on how this works a while back.
Adding variable delay wipers to a W123 If you are having trouble with the intermittent, and swapping N10 does not help, then chances are the park/run switch is the issue.
210 it is integrated into the N10 and K4/1 front SAM in the back of the fuse box. There is no intermittent relay per se, there is only a high speed and low speed relay. The intermittent function is calculated from the logic in the front SAM. If you have a rain sensor the N10 gets CAN bus message about % obscurity from N72 the overhead control panel. The actual command to run the wiper is indirectly controlled from the stalk switch. The stalk switch does not switch the motor current, it only switches different resistors onto a control line that ends up in the ignition switch. In the switch the resistances are read and translated into CAN bus messages that go to the front SAM. The front SAM interprets these messages and closes the correct relays to operate the wiper motor as required.