Sometime in the late 1990's (I think...not real sure of the exact date), RWS quit stamping "born on dates" on their springers. USE to be they'd stamp the month and year, but I guess they just figured it would be one less step in the process.
So I'm guessing your potential buyer wants what ain't there.
Get a good magnifying glass and check the left side of the receiver above the trigger. "If" there's a date stamp it should be in that area. I say "if" because in late 2009 or early 2010, around the same time that the T06 trigger was released, Diana quit stamping the manufacture date on their guns for a few years.
I bought my T05 34 Pro Compact new in March of 2010 and it doesn't have a date stamp on it. It only has a "DE" stamp where the date stamp would normally be. So if your 48 doesn't have a date stamp it's possible that it may have been made during the time that they weren't stamping the date on them. If that's the case then I would guess, since it's a T05 model, it was probably made around 2009, possibly early 2010, since the T06 models were coming out in 2010.
I do not recall a .25 being made in the TO5 TRIGGER?
THE .25 was first made with the T01 as an RWS. IN 2013 the 52 was made special in the TO6 trigger for a DWC Group buy branded Diana/Vortec. On the left rear side of these guns was marked fang Dwc group buy. After that the gun was introduced to the public after the group buy as a Diana.
The first 48/52 in T01 was not a power house gun in .25. The gun was not a real hit due to the low power of a .25.
After 2013 the gun was to have the LW barrel.
Not saying that there was not a .25 TO made but being an old RWS/Diana fan, PLUS a .25 fan I should remember the TO5 .25. The .25 was not a real popular caliber . Close range yes. The old saying was .25 is a 25 yard gun. .25/25 yards killer.
I have build many .25 spring guns in various brands. 19 gr pellet @ 860 fps was what the 2013 Diana .25 was made to shoot.
Hatsan 135 was the best .25 with that huge power plant. RWS 350 with the .25 barrel was shooting around 750 fps. Accurate but not a cannon and the 350 has a longer stroke than the 48/52.
This RWS 52 .25 May have been a gun that was made in the transition of the T01/TO5 with few made? So if it's not a custom rebarrel the date would date to the first T05.
The .25 really shines in A PCP.
