When master and disciples had done feasting, old Gao brought out on a red lacquer tray two hundred taels of loose gold and silver, and offered them to the three elders for the expenses of the road;

散碎金銀 is broken silver — not coin, but lumps weighed out on a scale, which is how most money actually moved in Ming China. 為途中之費 takes 為 as wéi, as. Two hundred taels is a very large offer, several years of a labourer's wages, laid on a lacquer tray in front of men who beg for their rice.

and he brought out three cotton over-robes for outer garments as well.

褊衫 is an over-robe of the sort monks wear; 上蓋之衣 is an outer garment. The cloth is the fallback from the money, and it is about to fail in its turn.

Sanzang said: "We are mendicant monks. At a village we beg our rice, wherever we come we ask a meal. How should we dare take gold and silver and goods?"

行腳僧 is a monk who travels on foot — the word is literally "walking-feet monk." 化飯 is to beg one's rice from door to door. The refusal is doctrinally impeccable and arrives one line before his senior disciple does the exact opposite.

The Pilgrim stepped up, swept out his hand and took a fistful, and called: "Gao Cai! Yesterday you put yourself to the trouble of bringing my master here;

掄開手抓了一把 — he swings his arm out and takes a fistful. The novel does not pause, comment, or give Sanzang a reaction shot. 累你 takes 累 as lèi, to put to trouble.

today we have gained a disciple, and I have nothing to thank you with.

Gao Cai is the servant who guided Sanzang to the farm in the previous chapter, and who took the brunt of Wukong's teasing on the way.

Take this odd gold and silver for your guide's fee, and buy yourself a pair of straw sandals.

帶領錢 is a guide's fee — a real category of tip. 買草鞋穿, buy yourself some straw sandals: the smallest purchase a traveller can name, offered with a fistful of silver. The gap between the sum and the errand is the joke, and Wukong keeps a straight face throughout.

Hereafter, whenever there are monsters, put a few more of them my way, and I shall have more to thank you with." Gao Cai took it, knocked his head, and gave thanks for the gift.

多作成我幾個 — "make me up a few more" — as though monsters were commissions and Gao Cai were an agent. 哩 is li. And the real joke is at the bottom: Gao Cai kneels and knocks his head in thanks for money that was never Wukong's to give away.

Old Gao said again: "If the masters will not have gold and silver, I beg they will accept this coarse cloth with a smile, as a poor token of my heart."

笑納, "accept it with a smile," is the standard formula for pressing a gift on someone who is refusing it; it survives unchanged into modern polite Chinese. 聊表寸心, a poor token of an inch of heart.

Sanzang said again: "We who have left the household, if we take so much as a thread by way of bribe, must labour a thousand kalpas to make it good.

一絲之賄, a bribe the width of a silk thread; 千劫難修, a thousand ages of cultivation to work it off. A kalpa is an unimaginably long cosmic age, so the exchange rate is deliberately absurd. Sanzang means every syllable, and has not noticed the fistful of silver that left the tray a few sentences ago.

Only let us take a few of the cakes and fruit left over from the table, to serve as dry provision on the way, and that will be enough."

吃不了的餅果 takes 了 as liǎo, the can-not complement: what they could not finish. 乾糧 takes 乾 as gān, dry. The Tang monk accepts the leftovers, and with that the pilgrimage is provisioned.