It is hard with out pictures. I have seen them sell as low as 100 in similar condition as yours but since yours is an early one (First Batch BSA (LJ PAT)) I would pump the price up a bit. The missing screw aint too much of an issue, they are not expensive to buy. The chip can depend on big it is.
Just a rough ball park figure would be between £140 and £180. With images I could make a better judgement. The earliest Lincoln Jeffries I saw sold for £220. It was number 300 and I was ill that day and missed the auction, was quite upset........
Also 1994 is my birth year
Only if my wallet was fatter....
Also these prices are just my guesstimate, others may think differently.