Hello,
I was looking into this as I was trying to determine how to fill out the addresses in nearby hamlets. I went over to look at what they actually are in reality (see below). The best I can tell is that those are not real house names. Something like "Rožkalni"[1] is -- you can see it does not have either street or hamlet number, while surrounding houses do. Otherwise, they would be in "Vietvārdu datubāze"[2]. My experience has been that kadastrs.lv mangles addresses due to their own system shortcomings when they cannot organize them correctly for whatever reason and have to resort to novel naming schemes (my own property is like that where actual address is 10-5, but kadastrs lists it as 10D, though nobody, even utility contracts, list it that way).

In case of Silmala 223, the hamlet/village is "Silmala" and the house number is 223 without a street name. If it had a street number, it would likely be Rīgas iela 11 or something, but you wouldn't say "Rīgas iela 11" is the house name. With that "Rožkalni" example, you can see the nearby houses have both the street number and the hamlet number.

If we go by full modern property street plates, they (not that I checked every one) have a prominent number with additionally both hamlet name and street name listed.[3] Since OSM--in theory--goes by what we see on the ground, then we would expect the plate to say "Silmala 143" as a single name if that was the name. In fact, 223 is just a number plate[4] (though I realize we are only using it as example here). I find that this is the case for the properties in this and other nearby hamlets, like nearby Banga, Selga, etc. In fact, most have just a number[4][5] and some don't have anything visible.

[1] changeset/51827482#map=18/57.25089/24.45043
[2] https://vietvardi.lgia.gov.lv
[3] https://imgur.com/a/lOX5I
[4] https://imgur.com/ajSlhlB
[5] https://imgur.com/ARDZP19
[6] https://imgur.com/vYVZl3W