We have a big catalog, with several categories and few hundred items total.
It is highly technical, aimed for industry rather than the end user; each category is presented with an overview and then each item has it's own page with part numbers, dimensions, and other detailed information.
It is not an e-shop.

Calalog is currently inherited from the parent company, and with poor user experience - written in Flash, hard to handle; tries to look and feel like a printed book, not taking advantage of what online catalogues can bring.
The target audience tends to be highly skilled in mechanical engineering, but not so much computer usage.

Please, could you provide me with information about best practise in this particular appliaction, and if possible, some examples? Tangible and graphical, something I could show to the company owner and which could then be passed to a webmaker?

I tried to search, but all I came up with was too small-scale and end-user oritented.
I assume I can't link the real thing, so a sample Overwiev and Product page:
https://imgur.com/a/V6OUM

Thank you.