I replaced my incomplete set of knobs with some purchased from Antique Electronic Supply. They look better than the originals.
https://www.tubesandmore.com/products/knob-aluminum-set-screw-notched-tip-125-diameter
https://www.tubesandmore.com/products/knob-aluminum-notched-tip-indicator-set-screw-75-diameter
BTW, the 2 center knobs, on your pre-amp, appears to the from a VOX amplifier. You can sell those on Ebay.
https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=vox+amp+knob&_sacat=0
I still have have my incomplete set of Dynaco knobs - I just have to find them. If you are interested in them, just let me know.
https://www.tubesandmore.com/products/knob-aluminum-set-screw-notched-tip-125-diameter
https://www.tubesandmore.com/products/knob-aluminum-notched-tip-indicator-set-screw-75-diameter
BTW, the 2 center knobs, on your pre-amp, appears to the from a VOX amplifier. You can sell those on Ebay.
https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=vox+amp+knob&_sacat=0
I still have have my incomplete set of Dynaco knobs - I just have to find them. If you are interested in them, just let me know.