That depends...

If you pay for your SIC type rating will they guarantee employment for a period of say 12 months? Will they reimburse you over a period of 12 months?

Is the salary much higher than your average SIC lear gig which can warrant the initial cost of the training (think SWA type deal)?

Is there hope of moving into a PIC position in the near future with the full type at their cost?

I would say that unless this is your dream job I would not consider paying for my own type to be SIC on a lear....or any AC for that matter.