Older Map Card

[Old dog 417]

I'm wanting to purchase an older mapping card for my Hummingbird 788ci HD. It's my understanding that due to the age (7-8 years old) of this unit that

it has some issues running current mapping cards. The included maps just don't show enough as the contour lines are at about 10' spacing.

I realize this is a long-shot but I'm in hopes someone may still have a card in a nonworking unit or leftover from one that's been sold.

Looking for coverage primarily in the Midwest and of course,..I don't want to spend much on this occasional use unit.

I'm in Springfield. 

Tight lines and close shots,

OD