how much for a Hy-score sporter???

[mrjasonryan]

how much for a Hy-score sporter???
Can anyone help please me, i'm trying to price a so called mint condition Hy-score sporter, in the box,
This is the message i was sent:
While recently clearing out my deceased father-in-laws house i came across a air pistol, it is called New HY-SCORE Sporter With interchangeable Barrels, it is complete with the original box and on the side of the box it has a ticket with the marks PH/6A MK-2 .
Can you give me some idea of value.
I think £150 would be fair, (I JUST DONT KNOW)
he tells me also:
I see from at the Internet that these pistols that were only made in Kent England for only a couple of years in the 80s are becoming rare and collectible.

I HOPE YOU GUYS CAN HELP ME OUT ON THIS ONE

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