What is the generic code number of the 1977 Mercury Villager light bar bulbs?

The bulb for a 1995 Villager is a 2040-USA, a specialty, black tip halogen. I suspect the 1997 is the same. donsbulbs.com I haven't figure out where to get them yet. The Mercury villager uses four (4) 2040 bulbs. If you are in Canada you can get them at Canadian Tire stores at a cost of about 8.99 per bulb. If you are in the USA or to order online you can go to a NAPA auto parts store or napaonline.com. The cost there is about $12.99 per bulb. the bulbs last on average 500 hours