SINGAPORE, July 16 (Reuters) - Indonesian e-commerce firm Bukalapak has increased its IPO size by about a third to $1.5 billion, underscoring hot demand from investors for the country"s largest local issue, two sources familiar with the matter said on Friday. Until a few months ago, Bukalapak, the No.4 e-commerce company and Indonesia"s first tech unicorn to launch an IPO, was looking to raise just $300 million. That grew to $800 million and then to $1.13 billion last week as investors clamoured for a piece of the company. read more The listing comes at a time when the pandemic has boosted demand in Indonesia"s $40 billion e-commerce market. Bukalapak, focuses on micro, small and medium-sized enterprises, as it competes with bigger rivals Tokopedia, Sea Ltd"s (SE.N) Shopee and Alibaba"s Lazada. Bukalapak, which counts Singapore sovereign investor GIC (GIC.UL) and Microsoft (MSFT.O) among its backers, has attracted interest from long-only funds, domestic investors and sovereign wealth funds for its IPO, said one of the sources who was not authorised to speak publicly about the matter. There was no immediate response to a Reuters query sent to Bukalapak. The IPO is likely to be priced at the top end of its price range of 750 and 850 rupiah apiece, the sources said. The order books, which close on Monday, are already multiple times covered across the price range, the sources said, adding that the IPO will be raised to $1.5 billion or the maximum 25% of its market value, the sources said. Bukalapak is set to make its market debut on Aug. 6, kickstarting a lacklustre IPO sector in Southeast"s largest economy. GoTo, the merged entity of Tokopedia and ride-hailing and payments firm Gojek, is also planning an IPO. Sources have said GoTo is looking to raise at least $2 billion in pre-IPO funding in the next few months, which will be followed by a local listing. Bukalapak and GoTo"s debuts will turbocharge Indonesia"s long subdued IPO market, which stagnated further during the pandemic. Money raised via IPOs more than halved in 2020 to $470 million, according to Refinitiv data.