These are the mostly mechanicals that I own and they have been proven over the years to have a robust build quality. There are a few with aperture priority auto exposure (Autoreflex T, ES II, K2, LX, new F-1 & FM3A) but they have most of their shutter speeds available when the battery is exhausted. The FM3A of course is the only one with all of the shutter speeds available even then.
Full size image link -> Mostly mechanical
The OM-1, MX and LX are most definitely jewel like but they give no quarter to their weightier brethren.
Some of these were slightly over or near your limit but most were well below. It all depends on the condition. If you're not resigned to Nikon then there are a few great choices available to you.