https://spacedock.info/mod/442/Bluedog Design Bureau
This has some smaller SRB's and liquid engines, But so much more, its massive over 400 parts they say. It will run with PbC but I'm sure it would through the balance that Zee has put into PbC completely out a whack. Blue Dog used to have a small probe parts pack a long time ago. It looks like it may have got incorporated into this one, as I haven't seen that one for awhile. Bit Bluedog does good stuff.
I can't imagine Zee getting this one done for a long, long time, if he even decided to tackle it.
I was also looking for just a few smaller parts also. This is all I have seen that is for 1.6.1 so far.