Nice example with slightly modified paintwork), advertised on craigslist in August 2018 - asking only $7,250 USD. Check out the others on Classic Register's Chevy Vega Cosworth Register. 

At the time of sale, the seller noted the following comments:

1975 Cosworth Vega Dash #1930 Twin Cam 2.0L 16 Valve. This one has had a lot of things done over the years and there is documentation of everything done going all the way back the the original sale, to include the original window sticker and sales agreement. I am the 3rd owner. It runs and drives great. I have owned this one for 2 years. It has 47,706 showing on the odometer. I can provide additional pictures, just let me know what you want to see. It has had a few cosmetic changes done by a prior owner to include the hood and trunk lid stripe, different trim ideas on the sides and some pin striping that is different than stock. There is also a rear spoiler that was added and also an AM/FM/Cassette in dash unit with 2 rear speakers. Like most over 40 year old vehicles there are items that need addressed, the fuel gauge does not work, there are some minor leaks that could be improved on, the hatch struts need replaced and the swing-out quarter window seals are not in very good shape.