Is there a way to tell before checkout if there is "regional price differences"?

I have a friend on Steam who i get gifts for but because they are in the UK and i'm in Australia alot of the time i get the following error when i try to gift them an item

Due to regional price differences, the gift you are trying to send cannot be sent to the recipient's region.

it's not every game but i generally only find this out when i go to actually pay for the item on Steam which is already several clicks

Wishlist > Item > Add to Cart > Purchase as Gift > Selecting user > Continue > Gift Messages Options (at least 4 clicks unless i use Tab) > unticking save payment > Continue > Back to Steam > Back to Cart > Remove

that's already 15 clicks across ~10 pages and i keep doing this over and over again until i get lucky to find a game i'm happy to gift that doesn't give the error (generally a game i've enjoyed and believe they would enjoy too).

what i would like to know if there is a way to tell before checkout if there is "regional price differences" with the game i'm about to gift? ideally before i even add it to the chart?

I think SteamDB.info should be able to tell you if there are price differences between your currency and another country.

Search for the game you are thinking about gifting, and then click the "Prices" option on the left to see the various prices of the game in the different countries the game is offered in.

For example, here is Stardew Valley:

I don't think there is any official source on how big of a difference is acceptable, but one source claims anything greater than 10% can't be gifted across regions. SteamDB will at least give you an idea of any big price differences between regions.