If you are a serious collector "Sooner or later you will buy a Hayter" well that was one of Hayter's marketing slogans and indeed my recommendation to you!
The Hayterette was designed and brought to the market in 1957/8, machine No.1 being manufactured on 19th May 1958, the first 1903 machines were fitted with a Villiers Mk7F 98cc engine, but this was replaced in 1960 by a Briggs & Stratton.
There also appears to be an additional batch of 122 machines with villiers engines serial No's 8121-8242 and confirmed in Hayters parts manual, why this jump in numbers I am yet to discover, were they a special batch? Did they find old stock of the Villiers later in 1961? as 1961 started with No. 3917 & 1963 with 17774.
Reason for this post is that we normally only see the very occasional early machine appearing but remarkably two of the early ones with villiers engines from 1958/60 have just appeared on ebay & I'm hoping they will be acquired by club members rather than being scrapped, they are No.221 & No.8236 the latter being from the batch of 122 referred to above.
These early ones are very collectable machines & the basis of probably the best selling rotary mower of all time, hundreds of thousands sold over 62 years, having only ceased production in 2019.
Image below of an early Hayterette in our collection No.169.
Ebay machines here, let me know if you get one..