Hello we have some stumps under our deck that have a small bit of rot. They are Cyprus pine. 150mm square. Buried about 200mm deep in soil. 10 years old. The rest of the wood is unaffected and the post is still very sturdy & structurally sound. Aimed to use ronseal hardener and filler, and then use in ground paste to coat before backfilling. Unfortunately we can't seem to get ronseal products in Australia. Thoughts on an alternative / overall fix? Thank you!