Welcome oldguy.
The HEAVY was a specific model in the pre serial days. Here is the Ludwig catalog from 1967 showing prices and models:
[img]http://black.net.nz/cym2013/602-models.jpg[/img]
I've got one weight recorded for a 24" HEAVY of 3925g, and the Paiste Only Wiki has an entry of 3998g. That site is currently down and I presume the 3998g is an average of a few weights. My weights were all provided to the wiki a few years back, but I may have new weights that weren't in the wiki calculations. Expected median price based on 4 sales of 24" 602s with HEAVY ink still present: $450 ± $80.
Since older 602s usually have the model ink missing, it is helpful to give some context from other sales. For 24" 602 rides with MEDIUM RIDE ink or no ink, the range of weights goes 2636g - 3875g, with a median weight of 3480g. In comparison the Paiste Wiki entry is 3228g. Expected median price for these based on 31 sales is $410 ± $80. But remember that this category contains lots of cymbals where all the model ink has gone so there could be some HEAVY and some MEDIUM and even some THIN models mixed in there.
Then there is another specific model which is the MEDIUM. Again I have only one weight for a MEDIUM with ink intact: 3212g. The wiki doesn't even have the MEDIUM in the weight table. Expected median price for a MEDIUM with ink intact is $500 ± $80 based on 4 sales. The difference in numbers between sales and weights is because not everybody gives a weight.
I've got loads of data from 22" and smaller diameters and have done enough analysis to know that the key factors in predicting price include whether or not the ink is intact, overall condition, the weight (lower weights preferred), and whether it is a "less common model". However, there is an entanglement between being a "less common model" and having the model ink intact. Where I've got lots of data I can begin to untangle that, but not for 24" 602 cymbals.
Having HEAVY or MEDIUM or MEDIUM RIDE ink raises the expected price, as does having a lower weight. So the ordering
Rides $410 ± $80
HEAVY $450 ± $80
MEDIUM $500 ± $80
is probably just reflecting the presence of model ink on those specific HEAVY and MEDIUM models. Since condition matters, to get a more accurate price for yours we would need photos. But in the absence of further information I'd use $410 ± $80 as the best estimate. However, prices are quite variable so if you sell it you get what you get on the day.
If you do get a chance to weigh your cymbal please do post the weight. As you can see, weight data is rare on the ground for these and every additional weight helps.