I think the front subframe mounts for the 107 chassis are the same as used on the W114/115 cars and that subframe mount kit can be had for just a little over $100 and are pretty easy to change even with the engine in the car. I bought a Febi kit in the past year for a W115 for about that cost (same P/N as yours; 115 330 1875). Note that Febi may not be an OEM part, but was a reasonable replacement and I've been happy with them.

It wouldn't seem to make sense not to use those parts.

The longevity of these mounts is also quite good.