After 7 layers of Mod Podge (left strip) it's looking quite realistic. The PVA didn't turn out like I hoped it would. I'm going to try to add at least another 3 layers to get a pretty rought wind swept effect.
The Mod Podge hadn't dried fully when I took the photos, hence the white patches, but I'm hoping the photo shows the texture of it. I think it looks very realistic.