How do you find the value of national recreation products inc common stock purchase warrant which was merged into fuqua industries inc on 12-29-1978?

The warrants of course have long since expired.

They were the right to purchase shares of National Recreation Products, a non-consolidated subsidiary of National Industries which controlled around 90 percent of the NRP shares, at a price above the cash tender offer made by NI acquirer Fuqua Industries for the publicly held shares, and thus were formally worthless after the public shares of NRP were acquired.

Because public shares of National Recreation Products originally had been floated by National Industries (bundled together with the warrants) at a price higher than the subsequent cash buyout price from Fuqua and because the market for NRP was not very liquid, NRP shares and warrants traded well below the IPO price and significantly below the cash tender offer.

Disgruntled shareholders of NRP brought suit in Delaware Chancery court against Fuqua Industries arguing that Fuqua had paid less than the shares were worth, and warrantholders brought a related lawsuit. The lawsuits were eventually settled.

Fuqua finally paid an additional fraction of a dollar in cash to former NRP shareholders, and also paid approximately 5 cents in cash per warrant to warrantholders of record on a date near the time of the original tender offer. (The warrants continued trading after that date, but there was no compensation to those who purchased them after the cutoff date at the time of the tender offer for the NRP common.)

Presumably holders of warrants at the time of the NRP tender offer but who never received the settlement check, could obtain it from Fuqua Industries' successors.
Those who bought warrants after the tender offer cutoff date are out of luck.