the rifle looks complete period austrain made between the wars, do doubt

the original barrel was drilled out and a liner was soft soldered, imho this exclude any high power .22 caliber center fire cartridge. the austrian proof house would have never accept this. the rifle looks like a proper hunting rifle, a 22 lr conversion for hunting makes no sense. other small 22 lr bolt actions were cheap and easy to get then. someone make a target practise rifle here maybe for indoor shooting. I can forward your data to Josef Mötz in Austria who is an expert for such things

but you know the christmas days starting tomorrow and nothing will happen before new years days.