LeFusil,
Sorry can't help you with the names of other makers producing these distinctive actions. In fact I doubt that anybody was. Why duplicate Scott's action when one could buy it in in any state from a rough casting to a fully finished gun? However, I believe a multitude of gunmakers did precisely this, buying in the parts finished to the level at which they could economically take up the baton and finish the gun off.
As example is a classic Blanch-like styled gun that I have in at present for a complete make-over. Signed by H Clarke & Sons, Midland Gun Works it is a Blanch in all respects but maybe a little poorer in overall quality. All details are precisely as one would find them on a Blanch even though presumably finished in Birmingham rather than London (nominally!).
As regards the 'Block Safety', I think you are mistaken in attributing it to Needham & Hinton. Their patent described an extension to the trigger blade that in turn moved a rotating block to the striker (p. 122). On page 124 he describes the H&H int. sear shown in Holland & Robertson's patent no 5834 of 1887 explaining that, although illustrated, it was in use before the patent.
