I hit the catalogues last night;
Buck and Hickman 1935 has 2 pages of hacksaw frames.
it's around 50/50 between inline and pistol style handles. The most expensive
are the Eclipse 20T (older style as in eBay above) at 7/6
and the Millers Falls #12 at 13/6.
The Eclipse 60B (still common in the s/h market) is 2/6.
The cheapest saw (no brand given) is 1/8.
Turning to Miller Falls catalogue #42, which is their 70th Anniversary
edition of 1938, we find an astonishingly wide range of saws over 5 pages.
Inline handles form only 30% (ish) of this range.
The top of the line is their (declared) flagship, the #84 at £3.50,
followed closely by the #12 at £3.40. The other "closed handle"
design is the #48, which appears to be a lightened and cheapened
(but not much) #84 at $2.20.
The range extends all the way down to a adjustable inline handle
model, the #78, at $0.80.
Curiously, the MF #12 in B&H and the MF #12
in the MF 1938 catalogue are far from identical.
As an observation it seems odd that hacksaws (in the main) have pretty perfunctory handles,
whereas wood saws (both backed and hand styles) have highly evolved handles.
BugBear