1994 Buick Lesabre SECURITY AND STARTING

I have a 1994 Buick Lesabre. The key broke a while ago, but I did have the chip portion, so I could still use it. Since lost the chip while vehicle was parkied over the summer. I have been to the dealer 4 times for a replacement key, everytime they give me a different key, and tell me to try it. Costs 60 bucks each time. Its getting expensive. I am trying to find a way to by-pass the chip requirement on my car. Can you help me figure it out. Dealer tells me they can't match my chip code because it is model year prior to 1995 when they started tracking the code by VIN.