There are various sizes of oil gallery plugs. Blocks are not all machined the same. Some blocks use larger plugs than other blocks, in some locations. Be careful which "plug kit" you buy--you may or may not get the correct sizes of plugs.
The oil gallery plugs by the camshaft/timing chain area may be VENTED on some engines. This is a great idea for purging air from the oil gallery. Some folks think the vents are for "oiling the timing chain", but that's not correct. You can buy vented plugs, or use a tiny drill bit to vent the plugs in the "kit".
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A few months ago, these were about fifty cents per plug. Now they're two dollars.
Some folks are big on threading the end of the passages by the timing chain, and using a threaded pipe plug instead of the press-in soft plugs. I put the standard soft-plugs in using threadlocker as a sealant--Loctite 271 "Red" for example.