Here's an 1888 Liberty Head Nickel that I eyeballed in the LCS tray. It was a long time ago, almost two years. Cost: $0.50
Well, at least it's worth a nickle! Comparable condition - http://www.usacoinbook.com/item/1888-liberty-v-nickel-low-mintage-103631/
I can't make out the last digit in the date in your pics. I'm assuming in hand it is clear. If you can't make the last digit out, then its probably worth a dollar, tops. If you can make the last digit out, clearly, and there is no doubt that it is an 1888, then I'd probably grade your coin a Fair-2 (tops!). $5 might be a good price for it, if a little high. For 50 cents, you can't really go wrong Assuming it is, in fact an '88, that is a semi-key in low grades. In higher grades it garners much less of a premium (compared to many other dates).
@physics-fan3.14 I can make out the last digit in person, and it is indeed an 8. Any shot at a Poor-1 lowball?