Can you see the octal tube socket hole right next to the tuner? That was punched for an optional 6K6 audio output amp. You'd need to add an audio output transformer and volume pot, but man this would be so simple to add the amp stage right on your TV chassis. There may even be an extra control mounting hole on the front of your chassis? Fada made a model 925 TV only chassis that I'm pretty sure used the same basic chassis layout as your 895, which is why the hole for the optional audio output is there next to the tuner. I can post the schematic section from the 925 and you can wire it accordingly, that is if you're up for the challenge?
https://i.imgur.com/oFR1Zab.jpg