Heiloway NR 1078, left hand blade

I have a Heiloway NR 1078 that was crafted in 1983/4 time frame. It was crafted for me as a left handed player and name on the tip of the handle The handle reads N.R. 1078 Heiloway PATENTIERT  D. Damron.  I have had it stored in an army foot locker for 35 years. 

I was stationed in Bad Ibling, Ge from 1983 to 1985 when this blade was crafted by Mr. Heiloway. I only knew, that at the time, I felt it was an expensive investment to play at a higher level in the German/American table tenis league. After my first use of this blade, my game went to another level. I was told back then that I was lucky to have that blade. The blade seemed to have a life of its own as to how it was marveled after it. I am 64 now but, as a left handled blade, I have nobody to pass it down to and am not really interested in parting with it yet. Since posting my question on here I have had many offers to buy it from around the world. I am astounded by the request to purchase but they want me to come up with a value. How would such an item be apraised?