Thx Big Bart.
I found some source(s) for new nozzles. So the nozzle out of my original Lucas/Cav is a 6801036.
Searching on ebay, I found a
lot of 4 for $37.98 + $12 shipping. So a bit less than $100 for 8. These
appear to be from a factory in Hong Kong.
On Aliexpress, I
found them selling for around $7.20 apiece with $4 shipping, so about $62 for 8.
I also found this
lot of 12 for $48.60 + $16 shipping so about $65, or about $5.40 each delivered. The only thing is that the picture is different and they seem to be selling various different injectors in the same listing, but clicking on "6801036 GYM" doesn't make the picture change -- and I'm not sure what "GYM" is about. It's probably the correct nozzle but would want to confirm with seller first.
There are some other listings on aliexpress as well. Just search on 6801036.
edit: one might be able to obtain them for as little as $1 apiece
buying in bulk at alibaba.
I hope that helps someone.