Don't know the survival rate, but can provide a good guess as to how many were born:

Estimated total number of Triple Lock Hand Ejectors in 44 Spl Including Misc. Calibers, and 455 Mk II

The “.44 Hand Ejector 1st Model” ‘Triple Lock’ serial # range is generally accepted to be 1 to 15375. As usual, not every serial # was used. The great majority of these were commercial models chambered in .44 Spl with the odd .45 Colt, .44-40, etc. Also included in this range are 812 chambered in .455 Mk II, 666 of this 1st batch produced for the British and in category #1 below. Pre production TLs include about a dozen chambered in the experimental .45 S&W Spl for the Army trials of 1906, some of which were turned into club guns; club guns total 20 in the Club Gun book.

Total 44 & misc cal. TLs:
So we roughly have a 15375 .44 TL serial # range, less 666 .455 TL contract guns = something under 14709 as usual, then subtract an additional 146 .455 TLs made and sold commercially with the 1st batch of .455 TLs = 14563, and subtract the last batch of 691 .455 TLs sold commercially numbered in the 12000 to 13000 range of the original 1 to 15375 serial range to get us to the total remaining of 13872 produced in .44 Spl and misc calibers in the 1st Model serial range TLs for the commercial market.

Total 455 TLs:
So we have 666 British contract produced military .455 TLs, and we have 837 (146 + 691) in .455 Mk II sold commercially all in the 44 # range, plus 5461 military 455 TLs in the British contract serial range for a total of 6964 .455 TLs.

Total TLs all calibers:
That puts the total regular production of all commercial and contract TLs in all calibers and both serial ranges at something approximating 13872 + 837 + 666 + 5461 at 20836, including a dozen or so 45 S&W Special (45 Frankford prototypes for the Army trials of 1906) as near as I can figure. Recognizing however that not all serial #s were actually built.

NOTE: There have been sightings and reliable reports of 2nd models with numbers that are lower than the usual 2nd Model serial range and T/Ls that are higher than the usual T/L range.

Triple Lock Target Models
If one were to presume targets were likely somewhere between 5 and 10% of total commercial production, that's 730 to 1460 target models.

__________________
Jim
S&WCA #819