they made me go bkk and get an emergency one when that happened to me.cost £100 then had to get a new one when bk in the uk.its a 1 use and they take it off u when u return to uk ,but its ok for travel around anywhere but uk.
i go for 4 5 mth every winter for yrs they havent asked me once .!!.and i been on many airlines,they used to ask if u had a visa now n then but now its 60 on entry and u can extend it shouldnt be an issue
its also free to get the stamp transferred to the new passport at a immigration office .i done it when mine got rain damaged and had to get a new one as most the stamps got fudged lol. they gave me a new number too instead of a replacement passport .uk one.
its simple 60 days on entry .30 days extension. go over the border come back 60 more and extend 30 again . 6 mth and you dont need have 500k in bank . i go over the bridge at nong khai and back .35 us dollar for laos visa . but i hear u have to stay a few days now . loads of ways to do it . seems maybe by air is best .