my oil pressure is similar to that of yours i noticed it had came down a little, its alright when im driving its about 50/55 and when its hot on idle 20 sometimes 15 but never lower, didnt really see it as a problem, hed a build about 5k ago pump was new when the last guy built it which was only 2.5k miles before i bought it so i didnt bother changing it, i maybe drop my sump to see if theres a little debree but i doubt it as it would have done it straight away