Try CEO Emporium. My wife bought droolpads from them. The sell babywearing essentials as well as other accessories like teething/drool pads.
I think SSC-making stores also make accessories. Try Lelliebubb and IMA although I'm not really sure if they sell accessories separately
You can check: https://www.facebook.com/9monthsandbeyondph/ (former The Baby Depot Manila) https://www.facebook.com/fandrcreation/