1 of n Multisig Scriptless Scripts? I know MuSig makes n of n multisig  scriptless. However, can we also aggregate multiple internal public keys in one public key, and unlock funds using either one of the internal public keys?
MuSig does not support m-of-n multisig, so you should use a threshold signature scheme like this:
http://cacr.uwaterloo.ca/techreports/2001/corr2001-13.ps