Anyone know what type of paint this is?

[Munkeyface]

I have a canvas picture which no longer fits my Colour schedule. I have an idea to repaint the red for one more in keeping.

Is it acrylic paint?

Sorry photo here

Yes it looks like it

Hard to tell, but with that thickness there is a good chance it is acrylic.

To be on the safe side you could go over it in oil, as that can cover either oil or acrylic. I'd chance my arm with acrylic regardless, given the oil probably dried out long ago, and it looks varnished anyway. It depends how much you value the painting and potentially having your additions eventually crack.