Based on the looks of the main diaphragm and exhaust mushroom, the reg needs all it's rubber internal parts replaced. You may get away with reusing the HP seat. Odds are the LP seat is toast so you will need a new on, These are hard to find but Rob use to have a few NOS ones http://www.thescubamuseum.com/Online%20 ... ort=normal
Also, the over pressure valve (OPV) on this reg is NOT AN OPTION and since it has rubber internal parts, odds are it needs servicing. The second stage in this reg is an upstream design so you must have an OPV installed, otherwise if (when) the HP valve leaks, it can cause major damage at the worst time if the OPV is not installed. Keep in mind that the Nemrod is metric in design, the OPV has metric threads and the common 3/8-24 OPV will not fit. It's close but does not fit.