Several years ago I bought an assorted pack of A4 sheets of gasket material ranging from cork, through various thicknesses of different materials – Klinger Statite, Interface, Tesnit, Flexoid & Klingersil etc. Great to have to hand when the need arises – usually at a weekend when the shops are shut, not that there any places left around here that sell engineering supplies etc.
If needs must, don’t forget the breakfast cereal box, won’t do a head gasket but is a get out of trouble for less critical applications !!

While we are on the subject of gaskets, it’s as well to consider that as well as their sealing function they may perform a “spacing function”, as in setting the amount of pre-load on a bearing or shaft. Substituting “stuff from a tube” for a crankcase or gearbox cover, may result in the loss of required end float and a tight engine or gearbox.
Then there is their use to insulate, such as to reduce heat transfer. For example ,anyone who worked on Aspera vertical shaft engines in the 50s/60s will remember those thick gaskets between the cylinder block and the long right angle inlet manifold – the one that worked loose and attributed to difficult starting!

The ridger looks home made and not Howard 350 none of the others also not Howard 350 in my opinion