According to the internet, the pay of the top European orchestras: Berlin Philharmonic, Vienna Philharmonic, London Symphony is between half and two thirds the pay of the top US orchestras (San Francisco Symphony, LA Philharmonic, Chicago Symphony). In both Europe and the US, the pay drops quite sharply when you go below the top few orchestras. We know a fair number of the members of the San Francisco Symphony as well as several top flight musicians who have been temporary or substitute members of the SFS and other top orchestras. The latter have often been auditioning for years for the rare open positions that appear in the orchestra. Often there are several hundred top musicians who apply for position in the violin section. One violist we know, who was a violin student with our daughter from the age of 5 or 6, has served in year long substitute positions for both the SFS and Boston Symphony, and auditioned for the permanent position for both. She was regarded very highly by the members of the both symphonies, but came in second in both auditions. She has been playing for regional orchestras and local chamber music groups as well as teaching to cobble together a decent living. She is now in her early 40's.
In the old days, a member of one of the top orchestras would get a significant boost to their pay with the extra pay from recording sessions and royalties. The top orchestra in that regard was the Berlin Philharmonic where Karajan had a major contract with Deutsche Gramophon and the orchestra members would regularly make as much money from their recording activities as from their regular salary. No longer the case. Almost all the major orchestras now have their own labels and release recordings made at live concerts. There is no additional pay for these recorded concerts except for royalties which, of course, depend on the sales of the recordings. Occasionally a wealthy patron will contribute to finance a recording project like the Mahler symphonies that MTT did with the SFS in the early to mid 2000's. Those were mostly not live performances and the musicians did receive extra pay for the rehearsals and recording sessions.
Many classical labels now use lesser known orchestras for their recordings. One of the best examples is the recordings on the Channel Classics label which feature the Budapest Festival Orchestra and their music director Ivan Fischer, who generate fine performances and fine sounding recordings (even featuring multichannel recordings on SACD and downloads!).
Larry