adapting vintage 3-pin connection to something new

I have a c. 1960 telefunken stereo hi fi console system which includes a turntable. There is no line-out connection (just some speaker jacks using a style of connection I've never seen before). The output cable from the phono which connects to the rest of the system is a round connector with three pins. From the searching I have done, this appears to be the three-pin DIN connector (not XLR) that was common in Germany at the time this system was manufactured.

What I want to do is copy some old 78s to my computer using this turntable, but I'm having trouble determining just what adapter I should use. I can't seem to find any female 3-PIN-DIN-to-something-modern adapter (any suggestions for sources?) I did find some 5 PIN DIN adapters (according to the pin-out diagrams, I should be able to just break off the two additional pins to make it work), but I don't know if the modern 5-PIN DIN is physically compatible with that of the 1960s era.

My final, but less preferred, option would be to just build a connector and wire it with a couple rca cables or a stereo jack. Should I do this, do I need to wory about voltage problems? I hope not, since I'd be grabbing the signal before the amplifier, but I've never worked with audio from this era before.

Any suggestions or guidance would be much appreciated!

The output cable from the phono
Do you mean from the turntable to the input of the amplifier? That would be straight from the cartridge which you can't just feed into the computer. It needs to be amplified a bit and equalization applied. In other words you need a phono stage. You also need a catridge designed to play 78s.
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Thank you all for your guidance (and the Flashback Sales link!). It looks like these connectors are still fairly common in Europe -- I even identified my mystery speaker connector at the Flashback site there.

The cartridge is a ceramic cartridge (Telefunken T200). It has a diamond needle -- one of the flipover kind that has the 78 stylus on the other side.

Thank you,