World War II era german made shotgun

[CY09]

I have a custom (maybe) double barrel 12 gauge shotgun from WWII Germany. Stamped SULH1. Emil Diemb. Roechlins Special Stagl.. it hasn’t been fired since WWII. I’m looking for a gunsmith that I can trust
Not to break it while trying to figure why the right barrel firing pin won’t reset. Recommendations?

 

[AdvancedLaser]

Reulet Gunsmith in Covington