Here it goes a complete list of the destiny of the 14 Electras VARIG was operating by the time they were retired from its fleet:
Registre (the Brazilian one): PP-VJL
Series number: s/n 1024
Last Commercial service: 30th December 1991, São Paulo/Congonhas (CGH) - Rio de Janeiro/Santos Dumont (SDU).
Sold to Blue Airlines, from Zaire, as 9Q-CDK "Lodja Putu";
PP-VJM, s/n 1025, 29th December 1991 SDU-CGH, in exposition at Museu Aerospacial da FAB ("Musal"), in Rio de Janeiro;
PP-VJN, s/n 1037, 5th January 1992 CGH-SDU, sold to Blue Airlines as 9Q-CDI "Dominique Misenga";
PP-VJO, s/n 1041, 1st January 1992 CGH-SDU, sold to FilAir, also from Zaire, as 9Q-CXU;
PP-VJU, s/n 1119, 23rd December 1991 SDU-CGH, sold to Blue Airlines as 9Q-CDG "Chicapa Wa Masamba";
PP-VJV, s/n 1126, 28th November 1991 SDU-CGH, sold to New ACS from Tanzania as 9Q-CRS and later as 5H-ARM;
PP-VJW, s/n 1124, 29th December 1991 SDU-CGH, sold to InterLink Congo as HR-AMM;
PP-VLA, s/n 1139, 17th November 1991 SDU-CGH, sold to FilAir as 9Q-CGD;
PP-VLB, s/n 1137, 9th December 1991 CGH-SDU, sold to FilAir as 9Q-CUU;
PP-VLC, s/n 1093, 28th December 1991 SDU-CGH, sold to Blue Airlines as 9Q-CDL "Jean Mungala";
PP-VLX, s/n 1063, 5th January 1992 SDU-CGH, sold to Air Spray Ltd. from Canada as C-FQYB. This is the firefighter you refer;
PP-VLY, s/n 1073, 7th December 1991 SDU-CGH, sold to New ACS from Zaire as 9Q-CRM;
PP-VNJ, s/n 1050, 5th January 1992 SDU-CGH, sold to InterLink Congo as HR-AML;
PP-VNK, s/n 1040, 24th September 1991 SDU-CGH, sold to FilAir as 9Q-CDU.
Of those 14 ships, as of January 1999, 4 of them had crashed/had been put out of service in order to provide parts to others:
9Q-CCV (ex-PP-VJV) crashed in Kinshasa, Zaire, while owned by Trans Services AirLift in 21st January 1994;
9Q-CGD (ex-PP-VLA), FilAir, crashed in Angola in July 1994;
9Q-CDG (ex-PP-VJU), Blue Airlines, crashed in Kinshasa in 13th March 1995;
9Q-CDL (ex-PP-VLC), Blue Airlines, put out of service in order to be canibalized in 1995.
Also, there were reports about the abandon of several others ex-VARIG Electras in Africa, due to several factors, but mainly because the airlines stopped operations and no buyers were found for the aircraft.
"Are there any good sources of information on the history of VARIG's L-188s, online or otherwise?"
I suggest to magazine I used as source for answering this topic:
In Flap Internacional (a Brazilian aviation magazine) no. 316 from January 1999 there is an extense article (18 full pages) titled "Electras in Brazil", and it's very good: excelents pictures and a very complete database...
I hope this could help!
TP343, São Paulo, Brazil.