Does pin hole in woofer affect sound quality?

If you find a pin of the same diameter, you can put another 'mirror image' hole in the other speaker for balance.

Seriously, if it's a paper type cone, you can sand some wood, mix the sawdust with a little wood glue to create a filler paste. Then patch carefully. If need sand lightly and use a dark grey, black or suitably colored marker to blend in the color.

I would practice filling in pin holes in card stock to determine how much glue/dust ratio works best.

Although it sounds like a lot of fuss, if the cone is very smooth, then you don't want to add texture...so best to do as little as possible...you want to have the least amount of effect on resonance/mass/performance.

As mentioned, best to remove the speaker, apply a low stick tape to the back (scotch 811) of the cone, fill the front, lightly smooth/sand (only if needed).

Conversely, you can tape the front and fill the back if the woofer basket allows access. That might look cleaner.

Thank you everyone for your responses. I did repair the pin hole with a dab of black silicone and wiped it smooth with the diaphragm surface. The paper cones on the woofers still appear to be stiff and the surrounds still appear to be springy and strong enough. One tweeter no longer worked, so both tweeters in both speakers were replaced with the Peerless by Tymphany tweeters recommended to replace the originals. The oak tops have been re-glued to the cabinets and new grill foam has been ordered to replace the worn and saggy original covers. That should complete the restoration of the Time Windows. I plan to test them this afternoon and if I can figure out how to upload a photo to the blog, I will do so.

happy days are here again! congrats

Matching the pin holes with others evenly spaced could lend some legitimacy to the driver.