I agree. I googled and found 2 companies who dye leather shoes. One was between £44 to £59 depending on how quickly you want them. The other asks for you to submit info for a quote.
Dyeing leather shoes is not easy to do at home (as I have found out) and expensive if done professionally.
On the other hand, the posters who can't find navy shoes, sorry but google "navy shoes" really is the answer.