mozart wrote:
The best source for serial numbers is Frenchy's huge collection.
Not even an honorable mention?
Although I only have about 30 Arias, and not a full harddrive of images(but close!)
As for the questions asked, I have to disagree regarding that there is no obvious correlation with a date(more on this later in the post).
I'll get to my collection in a sec, but I'd just like to point out that I can't remember ever seeing a set-neck/neckthrough Aria with a letter prefix serial.
Code:
Aria:
PB-500(or 550) - I770xxx
ST-600D - B790xxx
CS-350 - D811xxx
JB-xxx - D790xxx
JB-xxx - F760xxx
JB-xxx - E760xxx (only 53 in difference in serial with the above one, this one having the lowest serial)
JB-xxxD - E780xxx
PB-xxx - I770xxx
PB-xxx - B760xxx
PB-xxx - E771xxx
PB-xxx - F76xxxx (image too poor to get the entire serial)
PB-xxx - H800xxx
PB-xxxD - E800xxx (147 in difference in serial with the above one, this one having the higher serial)
PB-xxxD - G800xxx (146 in difference in serial with the above one, this one having the lower serial)
ST-500 - H770xxx
ST-500 - E780xxx
ST-500VS - E780xxx (second digit is hard to read, could be a 6)
ST-500D - C801xxx
ST-500VS - K770xxx
ST-600 - E760xxx
ST-700 - L780xxx
ST-xxx - C802xxx
ST-xxx - C801xxx
ST-xxx - G760xxx
ST-xxx - C771xxx
ST-xxx - F771xxx (687 in difference in serial with the above one, this one having the lower serial)
TE-500CD - G800xxx
TE-500N - E760xxx
TE-500N - C760xxx (39 in difference in serial with the above one, this one having the higher serial)
TE-xxxD - C800xxx
Vantage:
AV-315B - D500xxx
X-77 - J400xxx
My assumption then is that these Aria serials follow the "standard" MIJ serialization where the letter stands for the month produced and the first two digits denotes the year.
By using those assumptions I haven't come across any discrepancies or odd-balls that aren't in catalogs for that year.
When it comes to Vantage it seems that the first digit denotes the year and I presume that the letter stands for month it was produced.
In my records I didn't find a single letter-prefix serial after 1981, but on the other hand I have very few samples of post 1984/85 guitars. Also I have very few images of Arias own designs that had bolt-on necks, but none of them apart from a CS have a letter prefix serial.
There seems to be a change with bolt-ons and serials around 1982 where the letter prefix disappear and then it's only the first digit that denotes the year. My earliest example, I think, is a 1981 ST-600D(108xxxx, odd looking neckplate, could be swapped out or a very early one before they stamped them with Aria Pro)
And after writing this I notice that the OP was only interested in 81-87 models