Scope Mount for Steyr LP50 HP Compact

This will be a very narrow search.

I want to install a red dot on my new Steyr LP50 HP compact. I know Steyr makes a small Picatinny that attaches down the barrel. However, I'd have to order that from Europe. I'd rather remove the rear sight assembly and place a small Picatinny rail. I've tried 3 different ones and nothing fits so far. It is a bummer to search for this on the net, purchase, and when it arrives it won't work.

Just hoping someone has dealt with this and knows of something that definitely works.

Here are two strategies. I prefer the Picatinny with the Fast Fire (I have that red dot). The other piece fits down the barrel further. It is the one that I can get from Europe.

Thanks

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Thanks
Roy